Which takes me to the point of this blog post - that the Synoptic Problem is unresolvable. Whatever solution is posed will always be a hypothesis, and there will always be problems with it. Why? Because we don't have first century manuscripts of our gospels let alone autographs. And the transmission process of this material involved more than simple copying. It was creative reperformance and this means that it relied on human memory - whether we are talking about oral transmission or written.
To put it plainly, we have no idea what the Gospel of Mark actually said in the first century, or the Gospels of Luke or Matthew. We might act like we do. But the truth is we don't. Our manuscript tradition is at best 3rd century, and variable particularly by geographic locations. To be honest, I don't even know where Mark was written, although I can make a fairly educated guess. Textual criticism has created a wonderful eclectic Greek text for all of us to use. But it isn't what Mark wrote. It isn't what Matthew wrote. And it isn't what Luke wrote. How we should handle this fact as a guild has yet to be worked out with any satisfaction. I think we mostly ignore it because dealing with the manuscript tradition is, well, just too complicated.
But this we know. The early Christians, consciously and unconsciously were adjusting and even editing their gospels in this time period. One of the things that they were doing is harmonizing the stories. This isn't just the operation of scribes doing so deliberately. It is also the function of human memory which tends to recall things through what the mind already knows. So if a person knows a particular version of a story, and he or she learns a new version, the new version is going to be recast in light of the old.
At some point, I think it is going to be necessary for those people who work on the Synoptic Problem to deal with these two issues. By this I mean, not gloss over them, not give them lip service, but really face them and try to figure out what that means when we are trying to understand first century composition of our gospels. It is my sincere hope that whatever else comes out of the Oxford lineup, this will.